ES2691264T3 - Injection molding nozzle with guide needles guided by guide bushings and injection molding device with such a nozzle - Google Patents

Abstract

Injection molding nozzle (1) for an injection molding device (100) for processing a fluid material (M), a) with a nozzle body (10) comprising a rear end (11) and a front end ( 12), in which the rear end (11) can be arranged next to a material inlet (110) and the front end (12) can be arranged in front of an injection mold plate (120), b) with at least two closing needles (21, 22, 23, 24) that pass through the nozzle body (10) from the rear end (11) to the front end (12), c) with a melt guide (13) for the fluid material (M) leading from the rear end (11) to the front end (12) of the nozzle body (10), said melt guide (13) flowing into the through holes (51, 52, 53, 54) corresponding of the closing needles (21, 22, 23, 24), and d) with a heating device (30) arranged in the body of the nozzle (10), characterized by. e) the arrangement of an independent guide bushing (41, 42, 43, 44) at the front end (12) of the nozzle body (10) for each of the closing needles (21, 22, 23, 24) , and because each guide bushing (41, 42, 43, 44) has a through hole axially aligned (51, 52, 53, 54) with the corresponding valve needle (21, 22, 23, 24) to accommodate the corresponding valve needle (21, 22, 23, 24), f) because the guide bushes (41, 42, 43, 44) are arranged next to each other and in contact with each other, and g) because each guide bushing (41, 42, 43, 44) comprises a sealing surface 61, 62, 63, 64) that radially surrounds the through hole (51, 52, 53, 54), which may be arranged to seal an injection gate (121, 122, 123, 124) located in an injection mold plate (120).

Description

DESCRIPTION

Injection molding nozzle with guide needles guided by guide bushings and injection molding device with such a nozzle 5

The invention relates to an injection molding nozzle with closing needles according to the preamble of claim 1 and an injection molding device according to claim 15.

Injection molding nozzles are commonly used in plastics processing. They constitute the interface between the hot side of the machine and the cold side of the mold. On the hot side of the machine a mass of molten plastic is supplied which is conducted to the injection molding nozzle through a feed channel. Then, the molten plastic mass is conducted to a cavity located on the cold side of the mold through a through channel located inside the injection molding nozzle. In general, the injection molding nozzle is mounted on the inlet side of the through hole on the machine side. On the side of the mold, the front end of the injection molding nozzle is placed inside or in front of the injection gate of a cavity. Therefore, the injection molding nozzle is exposed to strong thermal stresses. Other important requirements that an injection molding nozzle must meet are high pressure resistance and constant and uniform heating of the melt flowing through the nozzle. In addition, the front end of the injection molding nozzle must be sealed facing the side of the mold.

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The arrangement of the cavities inside the mold is of increasing importance. Due to the increasing cost of mold materials and the need to create smaller and smaller injection molded parts, several approaches have been proposed to reduce the distance between the injection gates.

25 Document DE 100 84 280 D1 shows an injection molding device with at least one heated nozzle extending forward to a nozzle housing hole located in a chilled injection mold plate. In the injection zone, between the heated nozzle and the surrounding refrigerated injection mold plate, an insulating groove is provided. The injection molding nozzle comprises a front end, a rear end and several holes for uniformly spaced valve needles that run from the rear end to the front end. In each hole for a valve needle there is an elongate valve needle that can be moved in a longitudinal direction capable of moving simultaneously between an open position and a closed position thanks to a drive. In addition, a hole for molten mass is provided in the injection molding nozzle which extends from a central inlet located at the rear end to the front end. There, a valve sleeve is housed in a recessed housing. This also has several holes for uniformly spaced valve needles that are aligned with the valve needle holes of the nozzle body. The hole for molten mass forks depending on the number of valve needles and the different holes for molten mass extend diagonally outward in the front area and each flow into a valve needle hole of the valve sleeve. Finally, the different holes for molten mass of the valve bushing lead to needle inserts that are fixed 40 by means of a common retaining bushing screwed into the front end of the nozzle body. Said retaining bushing also fixes the valve bushing. Finally, a nozzle plug is provided at the front end of the nozzle body, particularly in the retaining sleeve. Said nozzle seal covers all needle inserts and, therefore, also the closing needles. However, due to this, the closing needles are in a jointly hydraulically connected space, which has the disadvantage that the needle inserts located inside the nozzle plug are in a common drain. This causes negative thermal influences and soils the injection points. Another disadvantage is the common arrangement and fixation of needle inserts. Because of this, thermal and manufacturing tolerances cannot be compensated individually.

50 WO 2009/049419 A1 also refers to an injection molding nozzle with several closing needles. It features an externally heated nozzle body with a rear end and a front end. The rear end is connected to a material inlet, while the front end is located in front of an injection mold plate. At least two closing needles penetrate the nozzle body from the rear end to the front end, and the holes in the nozzle body simultaneously serve as a melt channel 55 for the closing needles. At the front end of the nozzle body, an independent guide bushing is provided for each closing needle. Each of these guide bushings has a through hole that is axially aligned with the corresponding valve needle. This through hole serves to accommodate the corresponding closing needle and to guide the melt. In addition, each guide bushing is located in a separate recess located at the front end of the nozzle body. A retaining bushing 60 screwed with a radial sealing surface retains each guide bushing in said recess. This surface of

Sealing corresponds to a sealing surface located on the tempered side of the tool. In this way, the injection molding nozzle is sealed in front of each of the injection gates. In this case, the relatively large space required by the retaining rings is a disadvantage. Due in particular to the intended screwed connection of the retaining rings on the nozzle body, they must be sufficiently separated from each other. In addition, screwing the retaining rings is laborious and complicated. The high number of components in the front of the injection molding nozzle makes it expensive. On the other hand, the retaining rings and their joints cannot be placed individually in front of the cavities. This causes frequent leaks.

Therefore, the objective of the present invention is to solve these and other disadvantages of the state of the art and to create an injection molding nozzle and an injection molding device that allows injection of injection gates very close to each other and which, at the same time, allows producing high quality injection points. Between the injection molding nozzle and the injection mold plate, a reliable seal must be ensured at all times, which also makes it possible to compensate for thermal and manufacturing tolerances. Another objective 15 of the invention is to allow economical manufacturing of both the injection molding nozzle and the injection molding device.

The main features of the invention are indicated in the characterizing part of claim 1 and in claim 15. Different configurations are subject to claims 2 to 14 and 16 and 17.

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Injection molding nozzle for an injection molding device to process a fluid material, injection molding nozzle for an injection molding device to process a fluid material, with a nozzle body comprising a rear end and a front end , in which the rear end can be arranged next to a material inlet and the front end can be arranged in front of an injection mold plate, with at least two closing needles that penetrate the nozzle body from the rear end to the front end, an independent guide bushing being arranged at the front end of the nozzle body for each of the closing needles, and in which each guide bushing has a through hole axially aligned with the corresponding valve needle for accommodate the corresponding valve needle, with a melt guide for the fluid material leading from the end up to 30 the front end of the nozzle body, said melt guide flowing into the corresponding through holes of the closing needles, and with a heating device disposed in the nozzle body, the invention provides that each guide bush comprises a sealing surface that radially surrounds the through hole, which can be arranged to seal an injection gate located on the injection mold plate.

35 In this case, the one-piece design of the guide bushings and the sealing surface is especially advantageous. This design allows the guide bushing to be manufactured economically. In addition, each of the through holes is sealed in front of the corresponding injection gate. In this way, the melt is prevented from agglomerating / agglutinating in the injection zone, as occurs in the state of the art when a common drain is provided around the injection gates. On the contrary, according to the invention, an insulation groove can be provided around each guide bushing, reducing thermal losses and maintaining a constant melting temperature of the plastic inside the guide bushes. In addition, very little space is required between the different guide bushings. This allows a minimum distance between the different injection gates. The independent sealing of each guide bush allows to produce particularly high quality injection points.

Four. Five

Each closing needle must be mounted so that it can move axially between a closed position and an open position. This allows the needles to unlock the different through holes. As required, the closing needles may have either a common drive disposed on the side of the rear end of the nozzle body, or each of the closing needles may have its own drive 50 arranged, likewise, on the side of the rear end of the nozzle body. A drive is particularly advantageous for cavities of the same size or for a common cavity located behind the injection dampers. If it is necessary for the sealing needles to have different opening times, it is preferable to use an individual drive for each sealing needle.

A parallel arrangement of the closing needles is particularly preferred. Alternatively, a radial arrangement can also be provided, that is, in the form of a star.

A refinement of the invention provides that each guide bushing is inserted into a separate hole in the front end of the injection molding nozzle. In this way, leaks between the different 60 guide bushings are avoided. In particular, the adjustment between the guide bushing and the corresponding independent hole can

machining individually. According to a more detailed configuration, each guide bushing is inserted into the corresponding hole in the front end of the nozzle body. Therefore, it is not necessary to screw the guide bushings. In this way, the guide bushings can be placed very close to each other.

5 In particular, a design that provides that each guide bushing is mounted telescopically extensible axially in the corresponding hole in the front end of the nozzle body offers other advantages. These advantages relate, in particular, to the tightness between the guide bushing and the injection gate. The telescopic connection makes it possible to compensate for thermal expansion, especially those of the nozzle body, the injection plate and, for example, a distributor. Each guide bushing can move axially in relation to the injection gate. In this way, leaks between the guide bushing and the injection gate are avoided.

The telescopic housing is preferably designed as a sliding joint. In this way, possible spills of the plastic melt between the corresponding hole in the front end of the body 15 of the nozzle and the guide bushing are avoided. Said sliding joint may be interrupted by at least one radial notch. The notch must be on the radial outer surface of the guide bushing, as it is easier to produce than radial notches on the radial inner surface of the nozzle body hole. The radial notches improve the tightness of the sliding joint. In addition, friction between the guide bushing and the surrounding hole is reduced. In this way, the telescopic insertion of the guide bushing into the corresponding hole is facilitated.

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To compensate for the thermal fluctuations of distance between the mold side and the machine side, an energy accumulator can be arranged between each guide bushing and the nozzle body, which applies force to the guide bushing in the opposite direction to that of the rear end of the nozzle body. Therefore, each guide bush has a generally fixed position in relation to the corresponding injection gate. Although irregular dilations occur, the joint between the guide bushing and the injection gate is always guaranteed. To prevent possible displacements between the injection gate and the outlet opening of the guide bushing, the sealing surface of each guide bushing must be at the base of the corresponding injection gate.

The flow of material through the guide bushing is particularly advantageous if the through hole of each guide bushing comprises, between the mouth of its feed channel and its sealing surface, it comprises a channel widening with a diameter greater than the needle of corresponding closure. In addition, each guide bushing must have, in the through hole, guide pins aligned in an axial direction that protrude to the exit area of the material to guide the corresponding closing needle. This allows precise guidance of the needle to the immediate vicinity of the injection point. In this way, an especially high quality of the injection points is achieved.

Alternatively or complementary to the arrangement of an energy accumulator between the nozzle body and each guide bushing, it is possible to apply force to each guide bushing in the direction of the injection mold plate 40 by means of a treadmill. Said treadmill is fixed on the side of the mold, that is, on the injection mold plate. Therefore, the guide bushings also have a generally fixed position in relation to the corresponding injection gate. Depending on the available installation space, a pinch can be provided for each guide bushing or several guide bushes can be fixed using a pinch. To simplify assembly, the guide bushes and / or the holes located at the front end of the nozzle body preferably comprise insert chamfers. Alternatively, the pin can also be fixed to the body of the nozzle and retain the guide bushings in its holes. The latter can be achieved by applying force or allowing some play for longitudinal thermal compensation. Thus, it is not necessary to pre-assemble the guide bushes on the injection mold plate.

A preferred embodiment of the invention provides that the melt guide forks in the area of the guide bushes. In this way, a main melt channel, which forms the melt guide, is created in the area of the rear end of the nozzle body. The main melt channel only forks when it reaches the area of the guide bushings. This ensures that a homogeneous and uniformly tempered plastic mass reaches the guide bushings. In this way it is possible to supply plastic of the same quality to the injection gates. In addition, the residence time of the plastic mass in the hot runner system is reduced. If a large number of closing needles are available, several main melt channels can also be provided to simplify distribution. In principle, a main melt channel of its own can also be assigned to a particular valve needle. Thus, for example, different injection pressures can be provided on different valve needles or even very different melts can be processed, such as in the injection molding of multiple components.

A refinement of the guide bushing provides that each guide bushing comprises a feed channel that does not run parallel to the through hole, which flows into the through hole and which is connected to the melt guide in the direction of flow. Said inclined feed channel can radially flow into the through hole of the guide bushing. In this way, the seals and guides susceptible to wear of the closing needles can be placed in the guide bushing. The guide bushings are easy to replace and the maintenance of the injection molding nozzle is especially simple. This ensures a constant melt channel, particularly in the area of the injection gate. In addition, the thermal separation between the injection molding nozzle and the injection mold plate is optimal.

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According to an improvement of the invention, a sliding joint is installed in the through hole of each guide bushing between the mouth of the feed channel and the rear end of the nozzle body, into which the corresponding closing needle of so that it can move axially. This makes it possible to reduce the part of the closing needle that is submerged in the plastic melt to an area inside the guide sleeve. Thus, the closing needle moves smoothly. In addition, the gasket can be easily replaced by changing the guide bushing.

In order to improve the sealing effect and reduce friction between the valve needle and the guide sleeve, each sliding joint can be interrupted, in the axial direction of the corresponding closing needle, by at least one extension section whose diameter is larger than that of the sliding joint.

From a manufacturing point of view, a design is preferred in which each sliding joint has a cylindrical perimeter oriented coaxially to the corresponding closing needle. The closing needle must also have a cylindrical perimeter.

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To seal the injection molding nozzle in the closed position, in the through hole of each guide hole, between the mouth of the feed channel and the side of the through hole away from the rear end of the nozzle body, an airtight surface of closure which, in the closed position of the corresponding closing needle, forms a seal with the latter. Both the sealing surface and the corresponding surface 30 of the closing needle must be tapered.

A particularly advantageous embodiment of the guide bushing is achieved by providing that the diameter of the through hole of each guide bushing, between the mouth of the feed channel and the sealing surface, is larger than the diameter of the corresponding closing needle. In this way, the plastic melt 35 supplied by the machine can reach the area of the sealing surface in the closed position. With this, the distance to the injection gate is minimal. Therefore, the time it takes for the molten mass to reach the injection gate is also reduced when the needle moves from the closed position to an open position. To achieve precise guidance of the closing needle, the area of the sealing surface, each guide bushing must have, particularly in the through hole, guide pins aligned in the axial direction 40 protruding to the area of the sealing surface of closing to guide the corresponding closing needle. This allows precise guidance of the closing needle to the immediate vicinity of the injection point. Thus, the wear of the closing needle is minimal. However, there are cavities aligned axially between the guide pins and the closing needle. Those serve as return channels. When the closing needle moves from the open position to the closed position, the material displaced by the closing needle can return in reverse flow through these return channels. This ensures that the pressure inside the cavity does not increase depending on the displacement of the closing needle. Therefore, the pressure inside the cavity can be adjusted precisely. And smaller actuators can be used to actuate the closing needle.

In addition, an embodiment of the invention provides that the feed channel of each guide bushing protrudes radially from the corresponding guide bushing in relation to the through hole. Thus, the through holes located in the nozzle body are not filled with plastic. In this way, the closing needles can move with special smoothness. This makes it possible to design the melt guide as a single melt channel without bifurcations from the rear end of the nozzle body to the area of the guide bushings. This melt channel can only be branched and connected in the direction of flow to the feed channel of each guide bush 55 in the vicinity of the guide bushings. This ensures a uniform quality of the plastic melt in each guide bushing.

The distance between two injection gates can be minimized by placing the through hole and the feed channel of each guide bushing in a common plane, in which the thickness of the guide bushing perpendicular to the plane is equal to the diameter of the through hole and / or the feed channel plus a minimum wall thickness

necessary. With this, the guide bushings can be placed particularly close to each other perpendicular to this plane. The minimum wall thickness is deduced, in particular, from the wall thickness necessary to absorb injection molding pressures.

5 To ensure a constant flow of material from the melt guide to the feed channels of the guide bushes, the guide bushes must be provided with a torsional protection. Thus, the feeding of the plastic melt to the feed channel of the guide sleeve is achieved. To prevent the hole between the nozzle body and the guide bushing from narrowing if the guide bushing moves axially, a widening of the feed channel can be provided on the side of the guide bushing or on the side of the dough guide 10 cast in the nozzle body. Said widening runs, particularly, axially. Even if there is a telescopic displacement of the guide bushing inside the nozzle body, the passage section will still be of sufficient size.

A minimum distance between the injection gates can be achieved by placing the guide bushings about 15 next to each other and in contact with each other.

Preferably, each guide bushing comprises a flange with radial outward orientation in its front zone. This allows the guide bushing to rest axially on the body of the nozzle and / or on the injection mold plate surrounding the injection gate.

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To achieve a minimum distance between the injection gates despite the flange, the flange must have opposite flattened side surfaces. These can be found in a plane parallel to the axial orientation of the corresponding closing needle. Ideally, the guide bushes are in contact with the flattened sides of this flange. The flattened sides of the flange must tangentially touch the minimum necessary diameter of the guide bushing. Thus, the flange does not protrude from the minimum diameter in the direction of the adjacent guide bushing. In addition, two flattened sides of two guide bushings located next to each other form a torsion protection for the guide bushings. This is particularly important if the plastic mass flows through a side feed channel, crosses the wall of the guide bushing and flows into its through hole.

30 In addition, the guide bushing can be fixed to the injection mold plate by a treadmill that is hooked behind the flange. Therefore, the guide bushing is fixed in relation to the injection mold plate.

To feed the plastic melt from a central nozzle or distributor of the machine, the melt guide may have an axially aligned feed hole at the rear end of the nozzle body. Alternatively, the rear end of the melt guide may have a feed hole radially aligned with the perimeter of the nozzle body.

Also, the invention relates to an injection molding nozzle for an injection molding device for processing a fluid material, with a nozzle body comprising a rear end and a front end, in which the rear end can be arranged next to an inlet of material and the front end can be arranged in front of an injection mold plate, with at least two closing needles that penetrate the nozzle body from the rear end to the front end, in which a guide of molten mass passes through the body of the nozzle from the rear end to the front end, in which a heating device is disposed in the body of the nozzle, in which an independent guide bushing is arranged at the front end of the body of the nozzle for each of the closing needles, and in which each guide bushing has a through hole aligned axially with the valve needle co corresponding to accommodate the corresponding valve needle, in which the melt guide empties into the corresponding through hole, and in which each guide bush comprises a sealing surface that radially surrounds the through hole, which can be arranged to seal so an injection gate located in the injection mold plate 50 is sealed, in which the rear end is arranged next to a material inlet, in which the front end is arranged in front of an injection mold plate and in which Each guide bushing is arranged with its sealing surface tightly in an independent injection gate.

Thus, an injection molding device is provided that allows injection of injection gates 55 very close to each other. This allows to produce high quality injection points. Reliable sealing between the injection molding nozzle and the injection mold plate is guaranteed at all times. In addition, the injection molding nozzle according to the present invention makes it possible to compensate for thermal and manufacturing tolerances. The reduced number of components at the front of the injection molding nozzle reduces the manufacturing costs of the injection molding device. In order to be able to inject a large number of injection points, 60 the number of guide bushings can be increased or, alternatively, an input of material that is a

distributor. The distributor allows to install several injection molding nozzles on one side of the machine and supply plastic melt to said nozzles.

According to a configuration of the distributor, this is formed by a distribution plate. The body of the injection molding nozzle can be fixed to this distributor. However, a floating radial installation of the nozzle body in the distributor is preferred. Thanks to the distributor, the injection molding device can have at least one second injection molding nozzle.

In another variant of the injection molding device, each guide bushing has, in its front part, a flange with radial orientation towards the outside and the guide bushing is fixed to the injection mold plate by means of a treadmill that engages behind the flange In this way, the guide bushing has an essentially fixed position in relation to the injection gate of the injection mold plate. This allows the thermal expansion of the injection molding nozzle or the injection molding device to be compensated without leakage in the sealing surface of the guide bushing. For assembly, at first, the guide bushings can be fixed to the injection mold plate by means of the plunger and then the nozzle body can be connected.

Other features, particularities and advantages of the invention are deduced from the text of the claims, as well as from the following description of embodiments by means of the drawings. They show:

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Fig. 1 a three-dimensional view of an injection molding device with an injection molding nozzle; Fig. 2 a three-dimensional longitudinal section that crosses the front area of an injection molding nozzle;

Fig. 3 a longitudinal section through the front area of an injection molding nozzle;

Fig. 4 a three-dimensional longitudinal section through a guide bushing and a closing needle;

Fig. 5 a longitudinal section through a front area of an injection molding nozzle and an injection mold plate; Y

Fig. 6 a three-dimensional longitudinal section that crosses the rear end of an injection molding nozzle.

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Fig. 1 shows an injection molding device 100 with an injection molding nozzle 1 in a three-dimensional view. This serves to process a fluid material M. The injection molding nozzle 1 has a nozzle body 10 comprising a rear end 11 and a front end 12. The rear end 11 is connected to a material inlet 110 and the front end 12 can be placed in front of an injection mold plate. Four closing needles 21,22,23,24 pass through the body of the nozzle 10 from the rear end 11 to the front end 12. Hidden by the closing needles 21,22,23,24, there is a melt guide 13 which goes from the rear end 11 to the front end 12 of the nozzle body 10.

A heating device 30 is arranged in the body of the nozzle 10. In particular, it radially surrounds the body of the nozzle 10. The heating device 30 can be connected by an electric heating connection 32. A thermal sensor is also provided. with an electrical connection for thermal sensor 33.

Each closing needle 21,22,23,24 has an independent guide bushing 41,42,43,44 at the front end 12 of the nozzle body 10. Each of these guide bushes 41,42,43,44 has a through hole 45 51.52.53.54 aligned axially with the corresponding valve needle 21.22.23.24 to accommodate the corresponding valve needle 21.22.23.24. The melt guide 13 hidden by the closing needles 21,22,23,24 flows into the through holes of the guide bushes 41,42,43,44

At the rear end 11, the body of the nozzle 10 is fixed to a distribution plate 112 a distributor 111 50 with a nozzle head 31. Inside the distribution plate 112, a distribution channel 114 leads to a hole Feed 19 of the melt channel 18 of the injection molding nozzle 1. This distribution channel 114 is connected to a central nozzle of the machine by means of a connection nozzle 113.

55 Furthermore, the closing needles 21,22,23,24 pass through the distribution plate 112 at the rear end 11 of the injection nozzle 1. On the side of the distribution plate 112 opposite the nozzle head 31, the needles of closing 21,22,23,24 are connected to a drive 140. This drive 140 is located linearly behind the closing needles 21,22,23,24. This is a common drive 140 for the closing needles 21,22,23,24. The sealing needles 21,22,23,24 are arranged in parallel and so that they can move 60 axially between a closed position and an open position.

Fig. 2 shows a three-dimensional longitudinal section that crosses the front end 12 of an injection molding nozzle 1. The injection molding nozzle 1 comprises a nozzle body 10 that runs from the rear end 11 to the front end 12. The front end 12 can be placed in front of an injection mold plate. As the figure also shows, two closing needles 21,22 pass through the body of the nozzle 10 from the rear end 11 to the front end12. In addition, a melt guide 13 leads from the rear end 11 to the front end 12.

A heating device 30 is arranged in the body of the nozzle 10. The latter radially surrounds the body 10 of the nozzle 10. In particular, the heating device 30 is a thin film heater. At the front end 12 of the nozzle body 10, there is an independent guide bushing 41.42 for each closing needle 21.22. Each guide bushing 41.42 has a through hole 51.52 aligned axially with the corresponding valve needle 21.22. The melt guide 13 flows into the through hole 51.52 of the guide bushes 41.42. Each of the guide bushes 41.42 comprises a sealing surface 61.62 that radially surrounds the through hole 51.52. This can be arranged to tightly seal an injection gate located on the injection mold plate.

Sealing needles 21,22 are arranged in parallel and so that they can move axially between a closed position and an open position. The installation is carried out at the front end 12, 20 particularly by means of the guide bushes 41,42, which are inserted in a separate hole 14,15 at the front end 12 of the nozzle body 10. In particular, each guide bushing 41, 42 is inserted in the corresponding hole 14,15 at the front end 12 of the nozzle body 10. In addition, each guide bushing

41.42 is mounted telescopically extensible axially in the corresponding hole 14,15. Each of these telescopic housings is designed as a sliding joint. Since the guide bushings 41.42

25 are telescopically extensible, have a generally fixed position in relation to the corresponding injection gate.

The melt guide 13 comprises a melt channel 18. The melt guide 13 forks in the area of the guide bushes 41,42. Each guide bushing 41.42 comprises a feed channel 71.72 that does not run parallel to the through hole 51.52. This flows into the through hole 51.52 of the guide bushes

41.42 and is connected to the melt guide 13 in the direction of flow. Therefore, the feed channel 71.72 of each guide bushing 41.42 protrudes radially from the corresponding guide bushing 41.42 relative to the through hole 51.52.

35 The through hole 51.52 and the feed channel 71.72 of each guide bushing are in a common plane. The thickness of the guide sleeve 41.42 perpendicular to the plane is the same as the diameter of the through hole 51.52 plus a minimum necessary wall thickness.

In addition, each guide sleeve 41,42 has a flange with radial orientation towards the outside 25. This flange 25 40, in turn, comprises a flattened side. This is in a plane parallel to the axial orientation of the corresponding closing needle 21,22. Guide bushings 41.42 are in contact with the flattened sides of flange 25. With this, guide bushings 41.42 are protected against twisting.

Fig. 3 shows a longitudinal section through the front end 12 of an injection molding nozzle 1. The injection molding nozzle 1 comprises a nozzle body 10 which runs from a rear end 11 to a front end 12. The rear end 11 can be placed next to a material inlet and the front end 12 can be placed in front of an injection mold plate. Four closing needles

21,22,23,24 pass through the body of the nozzle 10 from the rear end 11 to the front end 12. For this purpose, the through holes 26,27,28,29 are provided in the body of the nozzle 10. In this In view, a melt guide 50 is shown which runs from the rear end 11 to the front end 12 of the nozzle body 10. Furthermore, the body of the nozzle 10 is radially surrounded by a heating device 30.

At the front end 12 of the body of the nozzle 10, there is an independent guide bushing 41,42, 43,44 for each closing needle 21,22,23,24. Each of these guide bushings 41,42,43,44 has a through hole 55 51,52,53,54 aligned axially with the corresponding valve needle 21,22,23,24 to accommodate the corresponding valve needle 21 , 22,23,24. The melt guide that does not appear in the figure flows into these through holes 51,52,53,54. In addition, each of the guide bushes 41,42,43,44 comprises a sealing surface 61,62,63,64 that radially surrounds the through hole 51,52,53,54. This can be arranged to tightly seal an injection gate located on an injection mold plate. Both the closing needles 60 21,22,23,24 and the through holes 26,27,28,29 and the through hole 51,52,53,54 of the guide bushes

41.42.43.44 are aligned in parallel. The sealing needles 21,22,23,24 are installed so that they can move axially between a closed position and the open position S2 shown. Particularly, the installation of the closing needles is carried out by means of the guide bushes 41,42,43,44 which are inserted in an independent hole 14,15,16,17 at the front end 12 of the nozzle body 10. The insertion of the

5 bushings are made, in particular, by introducing them. For this, each guide bushing 41,42,43,44 is mounted telescopically extensible axially in the corresponding hole 14,15,16,17 at the front end 12 of the nozzle body 10. Each of these housings Telescopic is designed as a sliding joint. Thanks to the telescopic connection of the guide bushes 41,42,43,44, they can adopt a generally fixed position in relation to the corresponding injection gate.

10

Each guide bushing 41,42,43,44 comprises a feed channel 71,72,73,74 which does not run parallel to the through hole 51,52,53,54. It flows into the corresponding through hole 51.52.53.54 and is connected to the melt guide in the direction of flow. In the through hole 51.52.53.54 of each guide bushing 41.42.43.44, between the mouth 81.82.83.84 of the feed channel 71.72.73.74 and the rear end 11 of the body of the nozzle 10, a sliding joint 91.92.93.94 is installed, inside which the corresponding closing needle 21,22,23,24 is mounted so that it can move axially. The corresponding sliding joints 91.92.93.94 are interrupted by extension sections 85.86.87.88 axially of the corresponding closing needle 21,22,23,24. Its diameter is larger than that of the corresponding sliding joint 91,92,93,94. In addition, each sliding joint 91,92,93,94 has a cylindrical perimeter oriented in the direction 20 coaxial to the corresponding closing needle 21,22,23,24.

Inside the through hole 51.52.53.54 of each guide sleeve 41.42.43.44, between the mouth 81.82.83.84 of the feed channel 71.72.73.74 and the side of the through hole 51.52.53.54 away from the rear end 12 of the nozzle body 10, there is a sealing surface 95.96.97.98. In closed position 25 of the corresponding closing needle 21,22,23,24, this forms a joint with the latter. For this, each sealing surface 95,96,97,98 comprises the closing needle 21,22,23,24 inserted in the closed position. In particular, the sealing surfaces 95.96.97.98 are tapered for this purpose. That is, they have a cone-shaped design that widens in the direction of the rear end 11 of the nozzle body 10.

30 As the figure also shows, the diameter of the through hole 51.52.53.54 of each guide bushing 41.42.43.44, between the mouth 75.76.77.78 of the feed channel 71.72.73 , 74 and the sealing surface 95.96.97.98, is larger than the diameter of the corresponding closing needle 21,22,23,24.

Particularly close placement of the guide bushes 41,42,43,44 is achieved by placing the through hole 35 51,52,53,54 and the feed channel 71,72,73,74 of each guide bushing 41,42,43 , 44 in a common plane. A thickness B of the guide bushing 41.42.43.44 perpendicular to the plane is the same as the diameter of the through hole 51.52.53.54 plus a minimum necessary wall thickness, plus half the distance between adjacent holes 14,15,16.17 at the front end 12 of the nozzle body 10.

40 Fig. 4 shows a three-dimensional representation of a longitudinal section through a guide bushing

41.42.43.44 and a closing needle 21,22,23,24 in open position S2. This representation can be applied to several guide bushes 41,42,43,44 of an injection molding nozzle, so it has been marked with reference marks of several guide bushes 41,42,43,44.

45 This indicates the position provided inside the nozzle body, in which the closing needle

21.22.23.24 runs from the rear end 11 to the front end 12. The guide bushing 41,42,43,44 has a through hole 51,52,53,54 aligned axially with the corresponding closing needle

21.22.23.24 to accommodate the corresponding closing needle. In addition, the guide sleeve 41,42,43,44 comprises a sealing surface 61,62,63,64 that radially surrounds the through hole 51,52,53,54. In particular, this is

50 located at the front end 12 of the guide bushing 41,42,43,44. This allows the guide sleeve 41,42,43,44 to be arranged to tightly seal an injection gate located in an injection mold plate.

The guide bushing 41,42,43,44 comprises an external cylindrical perimeter in the direction of the rear end 11. Thanks to this, it can be inserted into a separate hole in the front end of a nozzle body, in particular by inserting it. Thanks to the design of the guide sleeve section 41,42,43,44 and the design of the housing hole of said section at the front end of the nozzle body, the guide sleeve 41,42,43,44 is mounted so telescopically extensible. To facilitate the assembly of the guide sleeve 41,42,43,44, it comprises an insert chamfer at the rear end 11. In addition, the telescopic housing is designed as a sliding joint 60. This sliding joint 91.92.93.94 is interrupted by three extension sections 85.86.87.88 in

axial direction of the corresponding closing needle 21,22,23,24. The diameter of said sections is larger than that of the corresponding sliding joint 91,92,93,94. This improves the tightness and reduces the friction between the closing needle 21,22,23,24 and the guide sleeve 41,42,43,44 during the movement from an open position S2 to a closed position.

5

The guide sleeve 41,42,43,44 comprises, in the area of the external cylindrical perimeter located at the rear end 11, a feed channel 71,72,73,74 which does not run parallel to the through hole 51,52,53 , 54. It flows into the corresponding through hole 51.52.53.54 and can be connected to a melt guide in the direction of flow. The mouth 81.82.83.84 of the feed channel 71.72.73.74 flows into the hole 10 through 51.52.53.54, in particular between the sliding joint 91.92.93.94 and the end front 12 of the guide sleeve

41.42.43.44. The inlet port of the feed channel 71.72.73.74 is located in the cylindrical cover of the rear end 11 of the guide sleeve 41,42,43,44. In particular, it is radially aligned.

In the through hole 51.52.53.54 of each guide sleeve 41.42.43.44, between the mouth 81.82.83.84 of the feed channel 15 71.72.73.74 and the side of the hole Through 51.52.53.54 away from the rear end 12 of the nozzle body, a sealing surface 95.96.97.98 is designed. In the closed position of the corresponding closing needle 21,22,23,24, this forms a joint with the latter. For this, the closing needle 21,22,23,24 comprises a conical tip 75,76,77,78 at its front end 12. The sealing surface 95,96,97,98 is also conical. Thus, the sealing surface 95.96.97.98 comprises the closing needle 20 21,22,23,24 inserted in the closed position.

The diameter of the through hole 51.52.53.54 of the guide sleeve 41.42.43.44, between the mouth 75.76.77.78 of the feed channel 71.72.73.74 and the sealing surface 95.96.97.98, is larger than the diameter of the closing needle 21,22,23,24. This widening of the channel 65,66,67,68 allows the plastic melt 25 to the sealing surface 95,96,97,98 inside the guide sleeve 41,42,43,44, even when the needle Closing 21,22,23,24 is in closed position.

To achieve precise guidance of the tip of the closing needle 21,22,23,24 even in the area of the sealing surface 95,96,97,98, the presence in the channel widening 65,66 is provided , 67.68, of 30 axially aligned guide pins 55.56.57.58 that protrude to the area of the sealing surface 95.96.97.98 to guide the closing needle 21.22.23 , 24.

In addition, there is a sealing surface 61.62.63.64 for sealing in front of an injection mold plate at the front end 12 of the guide sleeve 41.42.43.44.

35

Likewise, a flange with radial outward orientation 25 at the front end 12 of the guide bushing

41.42.43.44. This can be supported axially on a nozzle body or an injection gate.

The sealing surface 61.62.63.64 for sealing the guide bushing 41.42.43.44 in front of an injection mold plate is arranged frontally at the front end of the guide bushing 41.42.43.44. The distance between this sealing surface 61.62.63.64 and the sealing surface 95.96.97.98 inside the through hole 51.52.53.54 is minimized. This minimum is based on a minimum wall thickness necessary to guarantee the stability of the guide sleeve 41,42,43,44. In the center of the sealing surface 95.96.97.98 and the front sealing surface 61.62.63.64, there is a narrowed outlet opening 59 of the through hole 51.52.53.54.

Four. Five

Fig. 5 shows a longitudinal section through an injection molding nozzle 1 whose front end 12 is arranged in front of an injection mold plate 120. The injection molding nozzle 1 comprises a nozzle body 10 that runs from a rear end 11 to a front end 12. The rear end 11 can be located next to a material inlet. A closing needle 21,22,23,24 passes through the body of the nozzle 10 from the rear end 11 to the front end 12. A heating device 30 is located on the perimeter of the body of the nozzle 10.

The closing needle 21,22,23,24 has a guide bushing 41,42,43,44 at the front end 12 of the nozzle body 10. The guide bushing 41,42,43,44 has a through hole 51 , 52,53,54 aligned axially with the corresponding closing needle 21,22,23,24. In this through hole 51,52,53,54 a melt guide 13 flows through the nozzle body 10 from the rear end 11 towards the front end 12. The guide sleeve 41,42,43,44 comprises a surface sealing 61.62.63.64 radially surrounding the through hole 51.52.53.54. This is arranged to seal an injection gate 121,122,123,124 tightly located in the injection mold plate 120.

The guide sleeve 41,42,43,44 is inserted in a hole 14,15,16,17 located at the front end 12 of the nozzle body 10. This hole 14,15,16,17 has a cylindrical perimeter and runs in a coaxial direction to the corresponding closing needle 21,22,23,24. The guide sleeve 41,42,43,44 also comprises a cylindrical perimeter in the area of the hole 14,15,16,17. This allows the introduction of the guide sleeve 41,42,43,44 into the hole 14,15,16,17. In particular, the guide sleeve 41,42,43,44 is mounted telescopically extensible axially in the hole 14,15,16,17 at the front end 12 of the nozzle body 10. This telescopic housing is designed Like a sliding joint This allows the guide bushing 41,42,43,44 to be fixed to the injection mold plate 120 by means of a rammer 45,46,47,48. The latter is screwed to the injection mold plate 120 and hooks behind a flange 25 of the guide bushing 41,42,43,44. Thus, the guide bushing 41,42,43,44 presses 10 constantly against the corresponding sealing surface 61,62,63,64 of the injection mold plate 120. This makes it possible to compensate for the possible changes by longitudinal thermal expansion of the nozzle body 10.

In addition, the guide sleeve 41,42,43,44 comprises a feed channel 71,72,73,74 which does not run parallel to the through hole 51,52,53,54. It flows into the through hole 51.52.53.54 and is connected to the 15 melt guide 13 in the direction of flow. In turn, the melt guide 13 is designed as a melt channel 18 that only forks directly in the vicinity of the guide bushings 14, 15, 16, 17.

In the through hole 51.52.53.54 of the guide sleeve 41.42.43.44, between the mouth 81.82.83.84 of the feed channel 71.72.73.74 and the rear end 11 of the body of the nozzle 10, there is a sliding joint 20 91.92.93.94. The closing needle 21,22,23,24 located therein is installed so that it can move axially. The sliding joint 91,92,93,94 is interrupted by three extension sections 85,86,87,88 axially of the closing needle 21,22,23,24. Its diameter is larger than that of the corresponding sliding joint 91,92,93,94. In addition, the sliding joint 91.92.93.94 has a cylindrical perimeter oriented coaxially to the closing needle 21,22,23,24.

25

In the through hole 51.52.53.54 of the guide sleeve 41.42.43.44, between the mouth 81.82.83.84 of the feed channel 71.72.73.74 and the side of the through hole 51 52.53.54 away from the rear end 12 of the body of the nozzle 10, there is a sealing surface 95.96.97.98. In the closed position of the corresponding closing needle 21,22,23,24, this forms a seal with the sealing surface 95,96,97,98. For this reason, the sealing surface 95.96.97.98 is designed conically. That is, the sealing surface 95.96.97.98 has a cone-shaped design that widens in the direction of the rear end 11 of the nozzle body 10. The corresponding area of the closing needle 21,22, 23,24 is designed as a conical tip 75,76,77,78. In the closed position of the closing needle 21,22,23,24, the latter radially surrounds the sealing surface 95,96,97,98.

35

The through hole 51.52.53.54 of the guide sleeve 41.42.43.44, between the mouth 75.76.77.78 of the feed channel 71.72.73.74 and the sealing surface 95, 96.97.98, has a diameter greater than the diameter of the closing needle 21,22,23,24. In this channel widening 65.66.67.68, in the area of the sealing surface 95.96.97.98, guide pins are arranged aligned axially 40 55.56.57.58 that protrude up to the area of the sealing surface. These serve to precisely guide the tip of the closing needle 21,22,23,24.

Fig. 6 shows a three-dimensional longitudinal section that crosses the rear end 11 of an injection molding nozzle 1. In this end there is, in particular, a nozzle head 31 of a nozzle body 10 for fixing the injection molding nozzle 1 to a central nozzle of the machine or a distributor. In an area closer to the front end 12 of the nozzle body 10, it is surrounded by a radial heating device 30. This receives electrical energy through an electrical heating connection 32 that leads radially to the nozzle head 31. In parallel to this heating connection 32, an additional electrical connection for thermal sensor 33 leads to the nozzle head 31.

fifty

The closing needles 21,22,23,24 run along the body of the nozzle 10, from the rear end 11 towards the front end 12. As shown in the figure, the through holes 26,27,28, 29 inside the body of the nozzle 10, through which the closing needles 21,22,23,24 run, have a larger diameter than the closing needles 21,22,23,24. Only at the rear end 11 of the nozzle body 10, in particular in the area of the nozzle head 31, the bearing bushes 35,36,37,38 are inserted in the through holes 26,27,28,29 . For this, the through holes 26,27,28,29 have a slightly larger diameter at the rear end 11 than towards the front end 12. The bearing bushings 35, 36, 37, 38 comprise a bearing surface interrupted by several grooves annular This reduces friction between the closing needles 21,22,23,24 and the bearing bushings 35, 36, 37, 38. In addition, the bearing bushings 35, 36, 60 37, 38 form a joint whose effect is seen enhanced by radial grooves. Although in principle, I shouldn't

If a joint is required in this area, it provides effective protection in case of failure of another joint. This reduces the risk of flooding the injection molding mold 100 with plastic melt in the process of solidification. Thus, the closing needles 21,22,23,24 are housed in the bearing bushings 35,36,37,38 at the rear end 11 of the nozzle body 10 and in the guide bushings 41,42,43,44 which are outside the figure at the front end 5 12. In this way, all the housing points are easily replaceable. In addition, the friction of each closing needle 21,22,23,24 during movement from an open position S2 to a closed position is greatly reduced.

The invention is not limited to one of the embodiments described above, but can be modified in multiple ways. Among other things, the number of guide bushes and valve needles can be modified as necessary, several injection molding nozzles can be placed in a common distributor and the invention is not limited to an axial alignment of the valve needles and the corresponding accommodations. On the contrary, a radial arrangement of the closing needles can also be provided, whereby a torsional protection should be formed between a guide element of the nozzle body and one of the 15 guide bushings.

All the features and advantages that emerge from the claims, the description and the drawing, including constructive particularities, spatial arrangements and process steps, can be essential for the invention both in itself and also in the most different combinations.

twenty

Reference List

 one

 Injection molding nozzle

 41 First guide bushing

 10

 Nozzle body 42 Second guide bushing

 eleven

 Rear end 43 Third guide bushing

 12

 Front end 44 Fourth guide bushing

 13

 Melt Guide

 14

 First hole 45 First treadmill

 fifteen

 Second hole 46 Second treadmill

 16

 Third hole 47 Third treadmill

 17

 Fourth hole 48 Fourth treadmill

 18

 Melt channel

 19

 Feed hole 51 First through hole

 52 Second through hole

 twenty-one

 First closing needle 53 Third closing needle

 22

 Second closing needle 54 Fourth through hole

 2. 3

 Third closing needle

 24

 Fourth closing needle 55 First guide pin

 25

 Flange 56 Second Guide Pin

 251

 Flattened side 57 Third guide pin

 26

 First through hole 58 Fourth guide pin

 27

 Second through hole

 28

 Third through hole 61 First sealing surface

 29

 Fourth through hole 62 Second sealing surface

 63 Third sealing surface

 30

 Heating device 64 Fourth sealing surface

 31

 Nozzle head

 32

 Electrical heating connection 65 First channel widening

 33

 Electrical connection for thermal sensor 66 Second channel widening

 67 Third channel widening

 35

 First bearing bush 68 Fourth channel widening

 36

 Second bearing bushing

 37

 Third bearing bushing 71 First feed channel

 38

 Fourth bearing bushing 72 Second feed channel

 73

 Third feed channel 96 Second sealing surface

 74

 Fourth feed channel 97 Third sealing surface

 75

 First conical tip 98 Fourth sealing surface

 76

 Second conical tip

 77

 Third conical tip 100 Injection molding device

 78

 Fourth conical tip

 110 Material input

 81

 First mouth 111 Distributor

 82

 Second mouth 112 Distribution plate

 83

 Third mouth 113 Connection nozzle

 84

 Fourth mouth 114 Distribution channel

 85

 First extension section 120 Injection mold plate

 86

 Second extension section 121 First injection gate

 87

 Third extension section 122 Second injection gate

 88

 Fourth extension section 123 Third injection gate

 124 Fourth injection gate

 91

 First sliding joint

 92

 Second sliding joint 140 Drive

 93

 Third sliding joint

 94

 Fourth sliding joint B Guide bushing thickness

 M Fluid material

 95

 First sealing surface S2 Open position

Claims (15)

1. Injection molding nozzle (1) for an injection molding device (100) to process a fluid material (M), 5 a) with a nozzle body (10) comprising a rear end (11) and a front end (12), in which the rear end (11) can be arranged next to a material inlet (110) and the front end (12) can be arranged in front of an injection mold plate (120), b) with at least two closing needles (21, 22, 23, 24) that pass through the nozzle body (10) from the rear end 10 (11) to the front end (12), c) with a melt guide (13) for the fluid material (M) leading from the rear end (11) to the front end (12) of the nozzle body (10), said melt guide ( 13) in the corresponding through holes (51,52, 53, 54) of the closing needles (21,22, 23, 24), and d) with a heating device (30) disposed in the body of the nozzle (10), fifteen characterized by. e) the arrangement of an independent guide bushing (41, 42, 43, 44) at the front end (12) of the nozzle body (10) for each of the closing needles (21, 22, 23, 24) , and because each guide sleeve (41, 42, 43, 44) 20 has a through hole aligned axially (51, 52, 53, 54) with the corresponding valve needle (21, 22, 23, 24) to accommodate the corresponding valve needle (21,22, 23, 24), f) because the guide bushings (41,42, 43, 44) are arranged next to each other and in contact with each other, and g) because each guide bushing (41, 42, 43, 44) comprises a sealing surface 61, 62, 63, 64) that radially surrounds the through hole (51, 52, 53, 54), which can be arranged to seal watertight way a gate 25 injection (121, 122, 123, 124) located in an injection mold plate (120). 2. Injection molding nozzle (1) according to claim 1, characterized in that each guide bushing (41, 42, 43, 44) is inserted into a separate hole (14, 15, 16, 17) at the front end (12 ) of the nozzle body (10). 30 3. Injection molding nozzle (1) according to claim 2, characterized in that each guide bushing (41, 42, 43, 44) is inserted into the corresponding hole (14, 15, 16, 17) of the front end (12) of the nozzle body (10). Injection molding nozzle (1) according to one of claims 2 or 3, characterized in that each guide bushing (41,42, 43, 44) is mounted telescopically extensible axially in the corresponding hole (14, 15, 16, 17) of the front end (12) of the nozzle body (10). 5. Injection molding nozzle (1) according to one of the preceding claims, characterized in that the melt guide (13) forks in the area of the guide bushes (41,42, 43, 44). 6. Injection molding nozzle (1) according to one of the preceding claims, characterized because each guide bushing (41,42, 43, 44) comprises a feed channel (71, 72, 73, 74) that does not run parallel to the through hole (51, 52, 53, 54), which flows into the hole intern (51, 52, 53, 54) and that is 45 connected to the melt guide (13) in the direction of flow. 7. Injection molding nozzle (1) according to claim 6, characterized in that in the through hole (51, 52, 53, 54) of each guide bushing (41, 42, 43, 44), between the mouth (81, 82, 83, 84) of the feed channel (71, 72, 73, 74) and the rear end (11) of the nozzle body (10), a gasket is installed 50 (91, 92, 93, 94), in which the corresponding closing needle (21, 22, 23, 24) is mounted so that it can move axially. 8. Injection molding nozzle (1) according to claim 7, characterized in that each joint slide (91, 92, 93, 94) is interrupted axially of the corresponding closing needle (21, 22, 23, 24) 55 by at least one extension section (85, 86, 87, 88) whose diameter is larger than that of the sliding joint (91, 92, 93, 94). 9. Injection molding nozzle (1) according to one of claims 6 to 8, characterized in that the through hole (51, 52, 53, 54) of each guide bushing (41,42, 43, 44), between the mouth (81, 82, 83, 84) of 60 feed channel (71, 72, 73, 74) and the side of the through hole (51, 52, 53, 54) away from the rear end (12) of the body of the nozzle (10) has a sealing surface (95, 96, 97, 98) which, in the closed position of the corresponding closing needle (21,22, 23, 24), forms a joint with the latter . 10. Injection molding nozzle (1) according to claim 9, characterized in that the diameter of the through hole (51, 52, 53, 54) of each guide bushing (41,42, 43, 44), between the mouth ( 75, 76, 77, 78) of feed channel (71, 72, 73, 74) and the sealing surface (95, 96, 97, 98), is larger than the diameter of the corresponding closing needle (21,22, 23, 24) 11. Injection molding nozzle (1) according to one of claims 6 to 10, characterized in that the feed channel (71, 72, 73, 74) of each guide bushing (41, 42, 43, 44) protrudes radially of the cap corresponding guide (41,42, 43, 44) in relation to the through hole (51,52, 53, 54). 12. Injection molding nozzle (1) according to one of claims 6 to 11, characterized in that the through hole (51, 52, 53, 54) and the feed channel (71, 72, 73, 74) of each bush guide (41,42, 43, 44) 15 are in a common plane, in which the thickness (B) of the guide bushing (41, 42, 43, 44) perpendicular to the plane is equal to the diameter of the through hole (51, 52, 53, 54) and / or the feed channel (71, 72, 73, 74) plus a minimum wall thickness required. 13. Injection molding nozzle (1) according to one of the preceding claims, characterized 20 because the guide bushes (41, 42, 43, 44) are arranged in the nozzle body (10) and protected against twists 14. Injection molding nozzle (1) according to one of the preceding claims, characterized because each guide bushing (41,42, 43, 44) has, in its front part, a flange with radial orientation towards the 25 (25) comprising the opposite flattened side surfaces (251) on which each two guide bushings (41,42, 43, 44) rest against said flattened side surfaces (251). 15. Injection molding device (100) with an injection molding nozzle (1) according to one or more of the preceding claims, wherein the rear end (11) of the nozzle body (10) is located 30 in the material inlet (110), in which the front end (12) of the nozzle body (10) is arranged in front of the injection mold plate (120) and in which each guide bushing (41, 42, 43, 44) is arranged, with its sealing surface (61, 62, 63, 64) in a sealed manner, in a corresponding independent injection gate (121, 122, 123, 124). 16. Injection molding device (100) according to claim 15, characterized in that the material inlet (110) comprises a distributor (111). 17. Injection molding device (100) according to one of claims 15 or 16, characterized because each guide bushing (41,42, 43, 44) has, in its front part, a flange with radial orientation towards the outside (25) and because the guide bushing (41, 42, 43, 44) is fixed to the injection mold plate (120) by means of a treadmill (45, 46, 47, 48) that hooks behind the flange (25).